Port expanders store user settings in non-volatile memory

San Jose, Calif.Cypress Semiconductor Corp.'s I²C port expanders store all user settings in non-volatile memory, eliminating the need to reconfigure the device after each power-up.

The CY8C9520 has 20 expansion I/Os, 3-Kbytes of EEPROM and four pulse-width modulator (PWM) sources; the CY8C9540 has 40 expansion I/Os, 11-Kbytes of EEPROM and eight PWM sources; and the CY8C9560 has 60 expansion I/Os, 27-Kbytes of EEPROM and 16 PWM sources.

"Our solution offers more I/Os, more memory and better functionality than competing products, at the lowest price per I/O on the market," said Steve Gerber, director of marketing for Cypress's programmable system-on-chip (PSoC) business unit, in a statement.

The I²C port expanders use a proprietary extendable soft addressing algorithm that allows I²C configuration of up to 127 device addresses per bus. As a result, the devices can control thousands of bi-directional I/Os in any application such as in the computing, communications and industrial sectors.

The I²C port expanders are offered in industrial temperature ranges of -40° to +85°C, with an operating voltage range from 3-V to 5.25-V. They include an optional EEPROM write disable pin input, an interrupt output that indicates input pin level and PWM state changes and internal power-on reset. In addition, every I/O can connect to a PWM and a single register command stores current configuration as non-volatile defaults.

All of the devices are available in production volumes. The CY8C9520 is offered in a 28-pin SSOP package; the CY8C9540 comes in a 48-pin SSOP; and the CY8C9560 is offered in a 100-pin TQFP package. The CY8C9520 is priced at 99 cents in high volumes.